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Indmar 5.7L HO SS and 385-hp 6.0L HO SS
Gas Marine Engines

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Indmar Marine, renowned for its inboard engines for ski boats has introduced a saltwater series of small-block performance V-8s intended for runabouts, small and mid-size cruisers and sport fishing boats. The first contender is the 300-hp 5.7L HO SS. Its saltwater motor partner is the 385-hp 6.0L HO SS. For those who may be unfamiliar with the nomenclature, HO means high output as in great gobs of horsepower.

Both of these multi-port fuel injected torque monsters feature fully enclosed freshwater cooling. That means nasty water never sees the inside passages of the saltwater V8 cylinder block and heads. Other corrosion protection includes the judicious application of E-Coating, an advanced dipping process that more thoroughly encapsulates exterior and internal surfaces. With an E-Coat paint job inside and out, cast grey iron and paint chemically bond. As a result cracking and peeling are virtually eliminated. No big surprise on a saltwater motor, fasteners are high-grade stainless steel.

For easy maintenance access and bone-dry daily operation the starters and alternators are top-mounted. The crankshaft-driven water pump is machined from extreme corrosion resistant, naval bronze. The oil filter is remote-mounted so oil changes go easier. The advanced closed-cooling system is corrosion-free. Coolant tanks are easily accessible for topping off and maintenance. Strategically located sacrificial anodes protect the seawater transmission cooling system.

Remember early on when we said these two new Indmar V-8s were performance engines. How Indmar builds horsepower is as simple as the sea is salt. Its proprietary dual-plane intake manifold generates great gobs of low-end torque, yet also features a broad power band. Acceleration comes on seat of the pants strong. Another key component is Indmar's Extreme Tuned Exhaust (ETX), a performance exhaust system that pumps up horsepower by very nearly eliminating back pressure. Fabricated of cast aluminum, ETX manifolds are particularly lightweight. Even better, is their one-piece fabrication that outright eliminates exhaust risers and their notoriously leaky gaskets. ETX manifolds are water-jacketed which maintains them at a cooler temperature. Naturally they're port-tuned to maximize horsepower. Finally, the limited warranty term runs for three full years.